#include <stdio.h>
#include <math.h>

int main()
{
    double n, result;
    long long m;
    while (scanf("%lf%lld", &n, &m)==2)
    {
        result = 0.0;
        while (m--)
        {
            result += n;
            n = sqrt(n);
        }
        printf("%.2lf\n", result);
    }
    return 0;
}